Mathematics
NULL
Medium
Question
Boat speed to current is 36 : 5. Going with the current takes 5 hours 10 min; how long is the return against the current?
A
5 hours 50 min
B
6 hours
C
6 hours 50 min
✓ Official correct answer
D
12 hours 10 min
Community credibility
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A
5 hours 50 min
No member explanations yet for this option.
B
6 hours
No member explanations yet for this option.
C
6 hours 50 min
No member explanations yet for this option.
D
12 hours 10 min
No member explanations yet for this option.
Explanation
Downstream : upstream speeds = 41 : 31. Time upstream = (41/31) × (31/6) = 41/6 hours = 6 hours 50 min.